At half-time the score stood at 6-3 to the home team, a rather mournful log of proceedings in its own right, and an even gloomier echo of the half-way stage at Cardiff on Friday night. But this was no dirge; this was a genuine investment in the work that yields points at a later stage. It was miserly but it was encouraging, and the game truly came to life in the second half.

Even before the points began to flow, it swung deliciously between pain and pleasure. There are concerns about whether the likes of Johnny Sexton can extract much of the latter given the way the game is currently and thunderously played. What fun is there for one so exposed and relatively slight to be had in staring runners coming at him in the eye and going high in the tackle? Won’t you be concussed again, Johnny?

The answer came from the player himself. In the 27th minute, Billy Vunipola, No1 bulldozer in the depot of heavy machines, was heading his way, throttle open and snorting. Sexton stood his ground and did not flinch. They met and Billy spilled the ball. It may not count as fun as defined by the larger mass of the population on a Saturday afternoon but Sexton seemed to enjoy it. That’s why he goes high, he might say.

It might sound as if Billy came off second best. Well, on that occasion he did, but in general he was on top form, too powerful for a single defender to bring down. Not that he spent the entire game knocking people over. He spent the first few minutes in an almost hallucinatory world of being the one who would not commit to contact. Billy the dummy, who flipped and slipped his passes away.

It did not last. On cue, at the start of the second quarter, just when the Irish forwards could be heard on the ref’s microphone shouting that this was the moment to find a higher gear, Billy lowered the blade on his machine and began to clear the path.

He escaped from a maul, burst through one tackle and was only stopped by a joint-effort between Conor Murray and CJ Stander.

Billy hurt his wrist in the process – but it seemed that this might be another of his dummies. Within seconds he was on the move again, making the yards that set up the drive for the line by Dylan Hartley – a surge that ended just short.

There came after the interval another period of calm for the giant. In these opening minutes Ireland took play into areas where Billy does not easily go – the wider channels. On its way to Andrew Trimble and Keith Earls, the ball went through the hands of Stuart McCloskey and there were glimpses of a road-clearer on the other side, the centre who matches Billy pound for pound.

It was Ireland’s best period and their unexpected quest for width put them on the front foot. Whether there was a direct correlation between this width and England being reduced to 14 is debatable, but it was certainly indicative of a game coming to life, and the loss of James Haskell for a high shoulder tackle helped the process.

While the wing forward was away, Ireland took the lead. Murray at last could take a little breather from tackling duties and squeeze himself over.

Sexton converted, adding the points but helping bring England back to life.

The home team now entered their finest phase, full of incisive running and adventure. Their momentum would generate two tries and Billy was very much at the heart of the initial stages – not out wide but running through Josh van der Flier to set himself on a run at Sexton again.

Just after the outside-half had recovered from this latest assault he had to undergo another ordeal, this time from the altogether smaller Ben Youngs, who caught him a little late – almost imperceptibly so – from behind, just after Sexton had moved the ball on. When next the ball came his way, Sexton dropped it. Perhaps he had his eyes on the posts in anticipation of a long drop; perhaps he sensed another clout coming his way.

Praise for England’s defensive operation – fair and iffy – is almost taken for granted, but Jack Nowell would deserve a special mention for tracking back and tackling Robbie Henshaw at the corner, making the centre lose control of the ball as he reached for the line. The way England attacked the rucks under their crossbar – Danny Care would be sent to the sin-bin for a separate offence – spoke of a fury not to allow their line to be breached anywhere.

We should end with the man of the match. He wasn’t perfect, in that he dropped a couple of passes, or let the ball be bounced from his grasp, but he put in a full shift, tackling as hard as anyone to the very end.

Eddie Jones will have given his No8 a special pat on his big, broad and no doubt sore back for how he brought England to life. How he brought the game to life. Eddie reckons Billy is still learning the game. Well, he’s a fast learner. For somebody who does not look built for speed, Billy pushed England at pace to a level not seen before in this Six Nations.

England’s Billy Vunipola stands out in Six Nations defeat of Ireland

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